NativeAOT-LLVM: Reinstate SingleEntry.targets

[yowl]

This PR, adds back SingleEntry.targets to src\coreclr\nativeaot\BuildIntegration\Microsoft.DotNet.ILCompiler.LLVM.targets and basically copies part of what was NeedNativePublishSupportForSDK6 to NeedNativePublishSupportForLLVM. It also adds a call to ResolvePackageDependencies to get PackageDefinitions set.

Minor version update to the docs.

As I've replaced NeedNativePublishSupportForSDK6 I'm basically saying we are not supporting .net SDK 6.

Hopefully this will fix dotnet publish --self-contained -r browser-wasm, it does so locally:

E:\tmp\consolelocal>dotnet publish --self-contained -r browser-wasm /p:MSBuildEnableWorkloadResolver=false /bl
MSBuild version 17.5.0+6f08c67f3 for .NET
  Determining projects to restore...
  Restored E:\tmp\consolelocal\console.csproj (in 2.87 sec).
  console -> E:\tmp\consolelocal\bin\Debug\net7.0\browser-wasm\console.dll
  Generating native code
  LLVM bitcode generation finished in 69.78 seconds
  console -> E:\tmp\consolelocal\bin\Debug\net7.0\browser-wasm\publish\

E:\tmp\consolelocal>e:\github\emsdk\node\14.18.2_64bit\bin\node --stack-trace-limit=100 bin\Debug\net7.0\browser-wasm\native\console.js
Hello, World!
True

[yowl]

Cc @dotnet/nativeaot-llvm

[jkotas]

This should fix #2235. cc @kant2002

Looks good to me. @SingleAccretion Any additional feedback?

[SingleAccretion]

We should add a note somewhere in the user-facing documentation that PublishAot=true is not supported.

[SingleAccretion]

NeedNativePublishSupportForSDK6 will be deleted in dotnet/runtime#82568 at which point this will conflict a lot...

I think we should just unconditionally override ImportRuntimeIlcPackageTarget:

  <!-- NativeAOT-LLVM: override ImportRuntimeIlcPackageTarget to not depend on the SDK-provided ResolvedILCompilerPack item -->
  <PropertyGroup>
    <!-- EmitLegacyAssetsFileItems tells the SDK to generate PackageDefinitions -->
    <EmitLegacyAssetsFileItems>true</EmitLegacyAssetsFileItems>
  </PropertyGroup>

  <Target Name="ImportRuntimeIlcPackageTarget" Condition="'$(BuildingFrameworkLibrary)' != 'true'" DependsOnTargets="$(ImportRuntimeIlcPackageTargetDependsOn)" BeforeTargets="Publish">
    <Error Condition="'@(PackageDefinitions)' == ''" Text="The PackageDefinitions ItemGroup is required for target ImportRuntimeIlcPackageTarget" />

    <PropertyGroup>
      <RuntimePackagePath Condition="'%(PackageDefinitions.Name)' == '$(RuntimeIlcPackageName)'">%(PackageDefinitions.ResolvedPath)</RuntimePackagePath>
      <IlcHostPackagePath Condition="'%(PackageDefinitions.Name)' == '$(IlcHostPackageName)'">%(PackageDefinitions.ResolvedPath)</IlcHostPackagePath>
    </PropertyGroup>

  </Target>

Before importing Microsoft.NETCore.Native.targets.

[yowl]

Thanks, have tried that and looks simpler.